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This content will become publicly available on May 9, 2019

Title: The relative viscosity of NaNO 3 and NaNO 2 aqueous solutions

In aqueous solution, both nitrate and nitrite are planar, monovalent, and have the same elements but different sizes and charge densities. Comparing the viscosity of NaNO 2 and NaNO 3 aqueous solutions provides an opportunity to determine the relative importance of anion size versus strength of anion interaction with water. The viscosity of aqueous NaNO 2 and NaNO 3 were measured over a temperature and concentration range relevant to nuclear waste processing. The viscosity of NaNO 2 solutions was consistently larger than NaNO 3 under all conditions, even though nitrate is larger than nitrite. This was interpreted in terms of quantum mechanical charge field molecular dynamics calculations that indicate that nitrite forms more and stronger hydrogen bonds with water per oxygen atom than nitrate. Furthermore, these hydrogen bonds inhibit rotational motion required for fluid flow, thus increasing the nitrite solution viscosity relative to that of an equivalent nitrate solution.
 [1] ;  [2] ;  [3]
  1. Washington River Protection Solutions, LLC, Richland, WA (United States)
  2. United States Dept. of Energy, Richland, WA (United States)
  3. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0167-7322; PII: S0167732218305993
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Molecular Liquids
Additional Journal Information:
Journal Name: Journal of Molecular Liquids; Journal ID: ISSN 0167-7322
Research Org:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org:
Country of Publication:
United States
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Sodium nitrate; Sodium nitrite; Viscosity; Hanford; Mode coupling
OSTI Identifier: